package io.github.dunwu.javacore.jdk8.stream;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

/**
 * @author Benjamin Winterberg
 */
public class Streams3 {

	public static final int MAX = 1000000;

	public static void main(String[] args) {
		sortSequential();
		sortParallel();
	}

	public static void sortSequential() {
		List<String> values = new ArrayList<>(MAX);
		for (int i = 0; i < MAX; i++) {
			UUID uuid = UUID.randomUUID();
			values.add(uuid.toString());
		}

		// sequential

		long t0 = System.nanoTime();

		long count = values.stream().sorted().count();
		System.out.println(count);

		long t1 = System.nanoTime();

		long millis = TimeUnit.NANOSECONDS.toMillis(t1 - t0);
		System.out.println(String.format("sequential sort took: %d ms", millis));
	}

	public static void sortParallel() {
		List<String> values = new ArrayList<>(MAX);
		for (int i = 0; i < MAX; i++) {
			UUID uuid = UUID.randomUUID();
			values.add(uuid.toString());
		}

		// sequential

		long t0 = System.nanoTime();

		long count = values.parallelStream().sorted().count();
		System.out.println(count);

		long t1 = System.nanoTime();

		long millis = TimeUnit.NANOSECONDS.toMillis(t1 - t0);
		System.out.println(String.format("parallel sort took: %d ms", millis));
	}

}
